The Top 10 Threats To Life On Earth

Nuclear Holocaust

Whenever one thinks of the next big global war, this is what comes to mind. | Source

Could This Possibly Happen In The Future?

A Hypothetical World War III Scenario

10. Global War

In 1945, the United States unleashed the full force of nuclear technology on Japan, dropping two atomic bombs on Hiroshima and Nagasaki respectfully. Each bomb literally destroyed its target and wiped out tens of thousands of people, leaving the survivors and their descendents to live with the effects of radiation exposure, which includes unnaturally high cases of cancer. It was in this moment, that humans achieved something that previously only nature was capable of; the ability to wipe out most living things including themselves. Thus far, the atomic bomb attack on Hiroshima and Nagasaki is the only example of a nuclear weapon being used in anger. However, the threat of it being used in such a fashion again is very real. In the early years of the Cold War, people lived in genuine fear of some sort of nuclear war between the two superpowers, the USA and the USSR, with the Cuban Missile Crisis in 1962, proving to be the culmination and justification of the widespread fear at the time.

Today, the threat of global war isn't quite as etched in our conscious as it was in the late 1950s and 60's, but the threat remains. In recent years, I've personally read reports about the possibility of India and Pakistan, both of whom possess nuclear weapons waging nuclear war against each other for control of Kashmir. Iran, who also possesses nuclear weapons, is mentioned regularly by the western media, but whether they pose any threat to the west is debatable, especially given the fact, that the current conflict engulfing the Middle East was initiated by the relatively new state of Israel. But for me, North Korea seems to be the most dangerous and unpredictable, and being a communist country they can count on the support of their mighty neighbour China by proxy.

It's hard to predict what will happen, people have been forecasting a Third World War ever since the conclusion of the Second World War in 1945. But what is certain is that wars and conflicts will increase, as precious natural resources such as oil decrease in number; furthermore the proliferation of nuclear weapons has significantly increased the risk that localised conflicts may morph into some sort of state sponsored global war over those aforementioned resources. Alternatively the spark could be lit by maverick groups of disaffected individuals, terrorists in other words.

The Reality Of Famine

The Story Behind The Famine That Gripped East Africa

9. Famine

Before the advent of agriculture, the concept of famine was virtually unheard in relation to human society. For most of human history, we have been hunter gatherers, and whenever they encountered a shortage of food or any other resources, they simply moved elsewhere. However, when humans started settling down and growing their food, their whole lives became invested in a relatively small area of land, and invested also, in only a few kinds of plants such as wheat and barley. Any kind of interruption to the growing and harvesting process always spells disaster for a settled community. They cannot simply move as hunter gatherers did, because more often than not, every other piece of fertile land has already been claimed by another farming community, and land left unclaimed has presumably been left due to it being unsuitable for agriculture (e.g. deserts, jungles etc.)

In recent times though, humanity has developed a technology so revolutionary that it can literally direct the process of evolution itself. It's the relatively modern science of genetic engineering. Scientists have successfully replicated life in a test tube by cloning cells; this has enabled them to essentially manufacture genetically modified crops to make them grow fitter, faster and larger. They have also stuffed them full of genes that render them totally resistant to both drought and disease. However, the deliberate manipulation of nature's age old operating systems is fiercely opposed by those who believe humans are not adequately equipped to take over from nature as custodians of Mother Earth. The fundamental fact is that humanity is a part of nature not separate from it, so the deliberate manipulation of precious resources could have dire consequences both for us and the rest of the natural world.

The Pox

A Bengali girl infected with smallpox in 1973. | Source

Will We Ever Experience Anything Like This Again?

The Spanish flu pandmic of 1918 killed more than 50 million people. At the time, this was equivalent to 5 per cent of the world's population. | Source

What A Global Pandemic May Look Like

8. Disease

With the adoption of agriculture, humanity gave up their wandering ways and settled down in fixed communities which eventually spawned the first town and cities. Right from the offset, humans shared these new settlements with recently domesticated animals such as cows, sheep and pigs. As a result of living in such close proximity with their animals, the people frequently fell victim to wholly new diseases that had jumped the species barrier. Many of these diseases are still prevalent today, including the common cold which originated in pigs. But the biggest killer in human history, in terms of disease is smallpox, a virus which originated some 12,000 years ago and jumped over to humans from cows.

To get an idea of just how destructive these 'diseases of agriculture' were to certain members of our species. We need to examine the age of European exploration, which began in 1492 with Columbus' first expedition to the Americas. The Europeans on board those ships all carried something far more deadly than any sword or spear; their bodies were full of diseases that had only arisen in those humans exposed to Eurasian agriculture and domestication. All in all, it's estimated that around sixty five human diseases came from dogs, more than fifty from cattle, forty six from sheep and goats and forty two (including influenza) from pigs. In less than three centuries more than 90 per cent of the Native American population was wiped out by the diseases of agriculture first brought over by the Spanish in the late 15th century, which made European conquest and colonisation of the continent much easier than it would have been had they faced a healthy population. However, bridges work two ways. The venereal disease syphilis was first recorded in Europe in the French armies invading Italy in 1494. It was probably introduced to Europe by sailors who returned from Columbus' first expedition, having contracted it from over intimate contact with Native American women. By 1498, following the voyages of Vasco de Gama, the disease had spread to India, and by 1505 it had reached as far as China.

Meanwhile, in recent times, in Africa, the HIV virus is destroying the human immune system, causing the deaths of millions of people who have been left defenceless against common infections. First diagnosed in 1981, the virus somehow jumped the species barrier from monkeys to humans. Since then it has killed more than twenty five million people, mostly Africans, and infected as many as forty six million more. There are currently more than a million orphaned children in South Africa alone, most of them are infected themselves, since their parents died from the disease and it's easily passed through body fluids such as breast milk.

Deep Contrasts

Via Rodeo in Beverly Hills, California, one of the most affluent cities on the planet. | Source

In stark contrast, while Jakarta, Indonesia can be classed as a developed city, it still retains large areas of slums. | Source

A Map Of Inequality

This is the Gini coefficient world map showing which countries have the best and worst in terms of equality of income. The number ranges between 0 and 1, with blue representing greater equality and reds and blacks representing greater inequality. | Source

7. Inequality

There seems to be a pattern emerging here, as once again we have a major threat to life on Earth brought about by the invention of agriculture. Hunter gatherers were egalitarian in almost every aspect of their lives, there were no chiefs, leaders or kings, there were no divisions of class or sex either. True, there was a rough division of labour with men commonly hunting and women commonly gathering, but it was a flexible division with women occasionally hunting and men occasionally gathering. We often think of hunting as the superior task, as it often conveys images of heroism and romance, but in actual fact it was extremely hard and dangerous. The reality was that the women were the lifeblood of a hunter gatherer tribe, collecting as much 80 per cent of all the food and resources required to sustain the community.

The status quo changed when people began to settle down; very quickly certain people realised that by controlling supplies of stored food and resources, they could assume power and force others to become dependents. The domestication of the horse further strengthened the gap in equality by giving some military superiority over others, and this was further reinforced by the manufacture of bronze weapons and chariots.

Today, in the present era, we live in a world dominated by capitalism, and while there can be no doubt that it has been highly beneficial to many of us, it also has a dark side. Hugely improved living standards for millions in some parts of the world hasn't rescued millions more from impoverishment elsewhere. By the end of 2001, the richest 2 per cent of adults in the world owned more than half of global household wealth, with the super-rich 1 per cent owning more than 40 per cent. Conversely, the bottom 40 per cent owned less than 1 per cent between them. It has been estimated that the richest 10 per cent of the world's adults now own more than 85 per cent of its total wealth. North America alone houses just 6 per cent of the world's population, but accounts for 34 per cent of all household wealth.

Today's inequality of wealth between individuals is mirrored by the differences between the world's richest and poorest nations. The scale of poverty in the Third World, particularly in post colonial Africa, shows no sign of lessening. The system of free trade, proudly trumpeted by advocates such as Ronald Reagan and Margaret Thatcher has proved in reality to be far from free. Massive subsidies for farmers in Europe under the Common Agricultural Policy (CAP), introduced in 1958, meant that the playing field was uneven. Poor countries in Africa, whose economies had been shaped by their colonial past, depended on income from food exports to feed their people. But the rich countries artificially depressed prices through subsidies and import taxes, claiming that they had to do so to protect the livelihoods of their own farmers, who produced as much food as they wanted for an inflated fixed price.

Mountains of European butter, lakes of wine, and stocks of cheese and grain that far exceeded what Europe itself could consume were dumped at rock bottom prices abroad, putting Third World farmers out of business. Although many of these market abuses have since been addressed, they have left a deep legacy of mistrust. Lacking an industrialised base, many poor countries have been forced to borrow funds from First World banks. Unable to pay back their loans, they have been caught in a vicious spiral of dependency. To add to their economic woes many colonies won their political independence only for their governments to fall into the hands of corrupt, despotic rulers, who, with weapons sold to them by developed nations, greedily clung to power. In this way, ethnic and tribal disputes still predominate today even after the tyranny or arbitrary colonial rule.

The Megafauna Extinction

Around 10,000 years ago, Ice Age icons such as the woolly mammoth, woolly rhino and sabre-tooth cat vanished as a direct result of human over-hunting. | Source

A Highly Recommended Link

What Killed the Megafauna?A hub written by me exploring the different theories that attempt to explain the demise of the megafauna.

The Symbol Of Extinction

The dodo was a flightless type of pigeon that was endemic to the island of Mauritius. It became extinct within a few years of human settlement. | Source

6. Shrinking Biodiversity

There can be little doubt that Planet Earth is in the midst of a mass extinction, which began as a barely noticeable trickle, but is now virtually an unstoppable torrent. The trickle began when hunter gatherer humans first left their ancestral home, Africa some 100,000 years ago and colonised the world. Each time, they arrived in a new land, there were extinctions, notably among the larger, slow moving and slow breeding animals; animals more popularly known as megafauna. The end of the ice age bore witness to the culmination of the megafauna extinction, which saw several very famous animals disappear forever, including the woolly mammoth and the sabre-tooth cat.

However, the end of the ice age also coincided with the discovery of agriculture, the advent of civilisation and the development of sophisticated technologies. In a relatively short space of time, humans, using these new technologies were able to colonise areas of the world which had previously been inaccessible to hunter gatherers, the oceanic islands for instance. These pioneering seafarers not only transported themselves, but a menagerie of animals and plants that they had depended on back in their homeland. The end result was both tragic and catastrophic, not only for the native flora and fauna, but for the human settlers. The story of Easter Island, and its transformation from a rich biological paradise into a barren windswept wasteland serves as an indication of the damage that humans are capable of inflicting.

Into the modern age, the technological juggernaut continues to run unabated. Once isolated communities have now become joined together, in only what can be described as a globalised world. Travel has never been easier, and as humans move around the world, so other living things get transported from one habitat to another. All of a sudden, species have to deal with the threat of a new predator or competitor, but without the time to adapt to survive many have and many more will become extinct. If that wasn’t enough, the sheer demand of trying to support a planet containing more than 7 billion people, has led to the loss of trees on a grand scale and the sterilisation of the soil through over farming. Furthermore the use of pesticides and over fishing are giving rise to the notion that humans are becoming increasingly vulnerable in a world that has long since lost its ecological balance.

Scenes Of Destruction

This is the last batch of sawnwood from a patch of forest cleared in Indonesia for the widespread planting of oil palm | Source

This photos the illegal destruction of forest in Madagascar, it also highlights the shifting slash and burn method used by the farmers. | Source

A Highly Recommended Link

How Deforestation Is Exterminating Our Cousins

5. Deforestation

The itch that led humans to settle down in fixed communities transformed how they regarded their environment. Previously, as hunter gatherers, they had simply regarded themselves as part of the landscape, but the development of farming and the concept of investing your entire life in a relatively small patch of land required the extensive destruction of wilderness areas in favour of cultivated land. In some areas this desire to tame the wilderness has had tragic consequences for both humanity and the rest of nature, with some areas becoming desert and scrub wastelands. In Africa, for example, over farming in the Sahel region is causing the already enormous Sahara Desert to expand southwards. China has had to resort to planting a huge ’green wall’ to hold back the expanding Gobi Desert; according to most sources, the project will take at least another forty years to complete.

Deforestation, especially in the tropics is the primary cause of the current mass extinction of species, with many iconic forest animals such as our great ape relatives projected to disappear from the wild in the next decade or so. Looking back in history, especially European history, the effects of deforestation are plain to see. At the end of the last Ice Age, a huge deciduous mixed forest covered virtually the entire continent, but as the millennia passed, the activities of humans caused the forest to shrink to the point where by Roman times it had virtually disappeared. Today this once great forest survives only in inaccessible mountainous areas, the only exception being the remarkable Bialowieza forest in eastern Poland, which has somehow remained standing without the protection of any nearby mountains. It serves as a last stand of the once great European wildwood. In recent times, humanity has made the startling discovery that widespread deforestation is damaging the Earth’s natural capacity to soak up climate changing carbon dioxide. Human scientists are also beginning to wonder whether major human tragedies, such as the Black Death, which wiped out more than half the population of Europe in the 14th century resulted in significant shifts in climate. Studies of atmospheric carbon dioxide levels in Greenland show a considerable reduction in the amount of carbon dioxide in the atmosphere, dropping from 282 parts per million in 1350 to 276 ppm in 1500. There was also a corresponding fall in temperatures during this period, which has for a long time been known as the ’Little Ice Age’. The most likely cause of this cooling was the massive reduction of the human population through the Black Death and the cessation of carbon producing activities such as agriculture, wood burning and deforestation.

One study suggests that the effects very nearly tipped the world into another major Ice Age- one that, although long overdue may now have been indefinitely postponed by the injection of vast amounts of carbon into the Earth’s atmosphere since the deforestation process began some 10,000 years ago, this process accelerated tremendously in the 18th century with the beginning of the Industrial Revolution and continues unabated today.

Planet Human

Dhaka, Bangladesh is among the most overcrowded cities in the world. It makes you think how on earth people can hear what they are thinking. | Source

How Things Have Changed

A graph recording the human population from 10,000 BC onwards. Note the unprecedented growth that started just after 1 AD and increased in the 19th century. | Source

How Many People Can Live On Planet Earth

More On Thomas Malthus

4. Overpopulation

For tens of thousands of years, the human population remained at a fairly stable five million. Then, with the birth of agriculture and the subsequent birth of civilisation, the human population spiralled out of control, which in turn piled huge pressure on the environment. By the time of Jesus Christ, a mere 8000 years after the first field was ploughed, the human population had increased to roughly 200 million.

By the beginning of the 19th century, the human population had almost reached the billion mark. At that time, an English economist called Thomas Malthus published an essay that predicted imminent disaster. He claimed that in fifty years, humanity would have increased to such an extent that there would not be sufficient food to sustain it. The problem that he had identified was that the human population was growing far quicker than the supply of food that the Earth could produce. If disasters resulting from human vices, such as war, didn’t cut humanity’s numbers sufficiently, then nature would take over, in the form of disease, famine and starvation, until the proportions of population to food supply regained a proper balance.

Modern man’s achievements would seem to suggest that he is indeed rather different from any other species that has ever lived. After all, what other living things have managed to interrupt, modify, compete with even and usurp nature’s age old operating systems? As for the dire warnings of Thomas Malthus; when he died in 1834, the human population had just passed the billion mark. By 1928 it had reached two billion; by 1961, three billion; by 1974, four billion; by 1987, five billion; by 1999, six billion and in 2011, seven billion. The growth rate is such that for each extra billion humans added, it takes roughly half as long to add a billion more. Dramatically falling child death rates have been accompanied by substantially longer life expectancy. Artificial fertilisers, medicines, improved hygiene, fossil fuels, industrialised cities, mass production, organic chemistry and vaccinations are the cause. It’s estimated that the world’s net population grows by approximately 211,090 every day.

Malthus was right. None of this would have ever happened if mother nature had had her way.

Ozone Damage

An image of the largest ever ozone hole ever recorded over Antarctica.

How The Greenhouse Effect Works

This Greenhouse effect schematic shows the energy flow between space, the atmosphere and the Earth's surface. | Source

David Attenborough Explains Man-Made Climate Change

3. Climate Change

History is full of great inventors, and choosing the greatest of them all is probably one of the hardest tasks you could ever asked to perform. But if you were asked to choose the unluckiest inventor of all time, then it would have to be one Thomas Midgley, he was an engineer who produced a new organic compound called tetra-ethyl lead (TEL). General Motors, the company that Midgley worked for found that it could be added to petrol to make engines run faster. But early on the effects of lead poisoning became apparent to Midgley, who was forced to take a year off work. Lead poisoning has been shown to cause insomnia, weight loss, learning difficulties and even premature senility.

Later on, after the TEL debacle, Midgley was working on looking for a new refrigerant for household appliances. He discovered how to synthesise chlorinated fluorocarbons (CFCs), which quickly became widely used in household fridges and sprays all over the world. But, it was found that these man made chemicals wreaked havoc in the Earth’s upper atmosphere.

CFC molecules are responsible for destroying the Earth’s ozone layer, allowing potentially lethal cancer producing ultraviolet radiation from the sun to flood down on to the Earth’s surface. So serious was this issue, that in 1987 almost every country agreed to stop CFC production. Nature has been left with the responsibility of repairing the damage, but the ironic thing is that the ban on CFCs may have exacerbated the issue of global warming since these chemicals at least provide some protection against infra-red radiation in the upper atmosphere.

What the above story shows is how the seemingly innocent actions of just one man can have such a profound impact on the world and its environment. Of course the current climate change episode that we are living through wasn’t caused by Midgley and his inventions. Instead its origins dwell in the mid 18th century when the Industrial Revolution began in central England. This marked the beginning of humanity taking on the guise of a massive volcano and pumping vast quantities of fossil fuels into the atmosphere. Back in 1750, the amount of carbon dioxide in the atmosphere was just 283 ppm, today the figure has jumped to 383 ppm. So it comes as little surprise to acknowledge that we live in a world of melting ice caps, shifting rainfall patterns, floods, droughts and extreme weather events that destroy harvests, settlements and lives. What will be the future consequences of climate change? Nobody knows for sure.

Air Pollution

Dense smog in a suburb of Taipei, Taiwan. | Source

How Pollution Affects The Human Body

An overview of the main health effects of the most common forms of pollution. | Source

An Overview Of The Great Pacific Garbage Patch

2. Man-Made Pollution

The Thomas Midgley story mentioned previously could easily be applied to the problem of man-made pollution. The main problem with such man-made materials is that are designed by humans, for humans, they have no intrinsic place or function in the world’s natural ecosystems. Nature’s products degrade and decay over time, so that she can re-use the planet’s raw materials without clogging up the Earth’s environment with waste. Most synthesized materials and artificial plastics do not biodegrade and often they can’t be recycled.

The problem of unnatural waste is well demonstrated by a process pioneered in 1839 by American inventor Charles Goodyear. By applying intense heat to natural rubber and mixing it with sulphur he concocted a new substance, vulcanised rubber, not found in nature, which was perfect for providing airtight elastic seals in machines like steam engines to make them run more efficiently. Later, this springy but durable material proved ideal for use as tyres on the wheels of bicycles and motorised vehicles. But because vulcanised rubber does not biodegrade, there is now such a mountain of worn out tyres that no one knows how they can be got rid of. By 2007, stockpiles of waste tyres had reached three billion in Europe and more than six billion in America, with 300 million more added each year.

Man-made pollution is also one of the main reasons for the overall rapid decline of biodiversity. Air pollution comes from the burning of fossil fuels, causing rainwater to become acidic. Metal foundries and petrochemical plants are sources of poisonous contaminants that destroy delicate ecosystems. Landfill sites release methane and harmful chemicals like cadmium, found in discarded electronic products, which poison the surrounding soil. In 2007 Britain had the worst record for landfill use in Europe, discarding some twenty seven million tonnes of waste into dumps that now extend across hundreds of square miles; and of course there’s the waste produced by the world’s 400 plus nuclear power plants which will remain highly toxic and harmful to the environment for up to 100,000 years.

More On Man-Made Pollution

The True End Of The World

If one of these collides with the Earth again, it'll mark the end of the world as we know it. | Source

1. Meteorite Strike

65 million years, a massive meteor measuring 6 miles across slammed into the Gulf of Mexico with the force of ten billion atomic bombs. The shock-waves were so great that they spread right across the world, half of the world’s plants erupted in flames, and the blast front was so thick, that precious sunlight was denied passage to the Earth’s surface for more than a decade, resulting in a bitter nuclear winter that was sufficient to wipe out nearly 70 per cent of all life. The most famous victims were the giant dinosaurs, with the birds representing all that’s left of a once mighty dynasty. The other casualties included all of the famous marine reptiles, all of the flying pterosaurs and the iconic ammonites, which had previously been very abundant and had survived the Permian Mass Extinction, which was actually much more severe in terms of casualties. The survivors all had certain common factors that ensured that they were perfectly equipped to survive in a post apocalyptic world; they were small, fast, hardy and capable of enduring long periods in a state of torpor (crocodiles, tortoises and their kin.)

Today most experts agree that it’s not a case of if such a thing will ever happen again, but when. At some point in the future, a massive meteor comparable in size to the dinosaur killer will smash into our fragile world, causing another mass extinction of species, which will probably include ourselves, given that we are large animals. We humans have delved into fantasy and dreamt up ways of possibly preventing this impending disaster, but the scary reality is that some of these killer objects are so dark in the vastness of space, that if one were headed our way, we would have little warning of the impending disaster.

Comments

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Ezria Copper 19 months ago

The blog I wrote deals with disease, inequality, air pollution, water pollution, to an extent-war. It is just that in that blog it deals with those things directly from a perspective of buying jewelry and what are some good companies to by from.

Cool dude 3 years ago

To be honest I'm worried about a global war and I will tell you why... Most of these threats won't be so series until the future but anyone could start a world war 3, which would be terrible and probably would mean the end of the world so if you're reading this don't go assassinating a president or something. But anyway if there won't be a world war 3 I'll most likely be dead before anything else

Author

James Kenny 5 years agofrom Birmingham, England

You're absolutely right Richard. It's interesting to note that apart from the biggest problem, all of the others are caused by mankind. You can't help but wonder what life would be like today if humanity had never evolved in the first place. Thanks for dropping by Richard. Merry Christmas!

Rich 5 years agofrom Kentucky

James - Interesting material. Man is a true killer, regardless of the method. His greed knows no boundaries when it comes to making the allmighty dollar. Most of what you write can be attributed to man's own doing. Perhaps, the meteor would only be just punishment for our acts. Great job! Have a great holiday!

Author

James Kenny 5 years agofrom Birmingham, England

Hi Ann, nice to hear from you again. Yes, you make a good point about global war. As resources dwindle, so greed, power and desperation will play an ever increasing role over where future wars are fought. Thanks for stopping by.

Ann Carr 5 years agofrom SW England

Wow! What an informative hub (as usual)! These things are scary but some are preventable. However, I think global war is the biggest threat as the nature of the beast is greed, the love of power and religious fanaticism; nor can we the ordinary people stop our politicians sticking their noses into other countries because they think, in their arrogance, that they know better. I hope I'm wrong but the signs are not good. Voted up, interesting, useful and awesome. Ann

Author

James Kenny 5 years agofrom Birmingham, England

To be honest, you could make a good case for all ten. But a meteor strike would effectively reset the evolutionary clock, which makes it stand out from the others. Thanks for popping by.

Margaret Perrottet 5 years agofrom Pennsauken, NJ

Given that nature has a way of balancing things out, I'd say that disease may be our biggest threat, although any one of the problems that you've covered could be our undoing. Excellent hub - voted up and interesting.

Author

James Kenny 5 years agofrom Birmingham, England

No problem Martin, that's alright. I'd probably be saying the same things if I was a bit older.

Martin Kloess 5 years agofrom San Francisco

Thank you for this informative hub. I hate to be self centered, but I only expect to be around a few more years. I have seen the changes...

Author

James Kenny 5 years agofrom Birmingham, England

Thanks Julie, yes the pandemic one is a concern because virus don't discriminate, and while they probably won't wipe us all out, they may end up destroying civilisation as we know it. Hopefully this one will end up like my other 'top 10' hubs. Thanks for popping by.

Jools99 5 years agofrom North-East UK

James, great hub. When you see them all in a list like this, it makes you feel a bit powerless! Almost any of these could spell the end of the world, but some will affect the rate of that demise faster than others. I always fear another pandemic because it is so random and can kill both young and old which is heartbreaking but war seems just as likely or the way we're ruining the earth. Interesting hub this one and I hope you get a comments 'deluge' soon and it might start some interesting debate :o)

Author

James Kenny 5 years agofrom Birmingham, England

Thanks Bill, but there is always hope. The Natural World has been through far worse than this in the past, and has always come through. It's the fate of humanity that worries me more than the fate of life.